History of Flow Meters
The concept of flow meters and flow measurement became known to people as early as a thousand years ago, particularly as water conservancy, farming, and irrigation became important to human civilizations.
Flow meters serve two purposes: the first is process control and check and the second is for improving product quality which reduces material costs and increases efficiency. Flow meters are frequently used in industries such as petrochemicals, pharmaceuticals, home energy, pulp and building, and metallurgy.
The development and use of flow meters have changed with time, but their requirement remains the same: precision and accuracy.
In ancient Egypt, people utilized weir rudiments to assess the flow of the Nile River. This provided an indication of whether the harvest would be favorable or unfavorable.
In China, around 256 BC, the State of Qin implemented the Dujiangyan irrigation system as a way to control floods and provide water conservation. The infrastructure of this irrigation system is located on the Min River which is the tributary of the Yangtze River. Before Dujiangyan irrigation system was implemented, water from the Min River would rush down the Min Mountains and abruptly reach the Chengdu Plain, causing an abrupt buildup of silt, leaving the area susceptible to flooding. The governor of the state of Qin and his son headed up the construction of the Dujiangyan irrigation system. It harnessed the power of the river by way of dividing and channeling the water instead of relying on the traditional dam building. This irrigations system is still in use today. It presently irrigates more than 5,300 square kilometers of land in the area.
In the 1700s, modern flow meters saw more enhanced development. In 1738, Swiss Daniel implemented differential pressure to judge water flow. Later on, in 1791, Italian researcher G. B. Venturi conducted studies on the Venturi tube to measure flow. His results were published later that year.
Much later in 1886, Hershel in the USA devised the Venturi device to effectively measure water flow in open channels. Parshall later changed the Venturi flume to a Parshall flume in 1922.
From 1911 to 1912, American Hungarians Tollbar devised a new theory called the Tollbar vortex. By the 1930s, ultrasonic flow meters were being utilized to measure liquid air flow velocity, but they did not achieve good results. In 1955 Maxon created the sound cycling method to accurately measure flow in aviation fuel.
Due to the limitations of technology and economy up to and during the 1950s, only Orifice plate flow meters were being used in all industries, including the rotate flow and pilot tube.
The 1960s saw the creation of instruments that leaned towards miniaturization and precision. As the 1990s appeared, the demand for flow meters took an upsurge. It was estimated that in 1989 alone, 15 million flow meters were mounted. Ultrasonic flow meters, in particular, saw advanced development.
Currently, there are more one hundred types of flow meters being used in the world. In the USA alone, there are more than 200 companies that produce flow meters.
Some of these are:
- Differential pressure flow meters
- Turbine flow meters
- Ultrasonic flow meters
- Rotary flow meters
- Vortex flow meters
- Positive displacement flow meter
- Thermal flow meter
- Coriolos mass flow meter
As the brief history of flow meters illustrates above, this is an important technology. They are used in a variety of industries around the globe and continue to be developed.